Reinforced tab



Nov. 19, 1968 F.' M. SILVER 3,411,662

REINFORCED TAB Filed March 27, 1967 Arman/5);!

United States Patent 3,411,662 REINFORCED TAB Francis M. Silver, Dayton, Ohio, assignor, by mesne assignments, to Ermal C. Fraze, Dayton, Ohio Filed Mar. 27, 1967, Ser. No. 625,993 16 Claims. (Cl. 22054) ABSTRACT OF THE DISCLOSURE This disclosure describes a reinforced tab of the type which is particularly adapted for use on an easy-opening container. The specific embodiment described herein includes a handle portion at one end, an attachment portion at the other end having a bottom wall with an aperture therethrough, and a sloping wall surrounding the bottom wall and extending upwardly therefrom radially outwardly of the aperture. A U-shaped lance is formed in the bottom wall and partially surrounds the aperture. Marginal portions of the tab are turned inwardly to form a bead that extends substantially completely around the tab. The bead is widened adjacent the attachment portion so that it is engageable with the sloping wall of the attachment portion to support the latter.

Background 0 the invention This invention relates to a tab construction for an easyopening container and more particularly to a reinforced front opening tab construction which is particularly adapted for use with easy-opening containers of the full panel pullout type.

Easy-opening containers of the full panel pullout type are becoming increasingly popular. The expression full panel pullout has reference to an easy-opening container wall or can end having a rupturable scoreline defining a removable panel. Typically, the removable panel covers nearly all or a major portion of the container wall.

A tab is secured to the panel by an integral rivet. The tab has a handle portion, an attachment portion for attaching the tab to the panel, and a rupturing end portion. By lifting the tab to initiate severance of the rup turable scoreline and then pulling outwardly on the tab, the entire panel is removed from the container wall. During the upward movement of the handle portion of the tab to rupture the scoreline, a bend line forms through a substantial segment of the panel. A panel segment of the panel bends about this bend line during upward movement of the tab. This bending of the panel segment requires the user to exert a substantial force on the tab. T0 at least partially compensate for this, tabs used on full panel pullouts usually have substantial length so as to increase the leverage which is obtainable to rupture the scoreline.

Because the length of the tab is increased and because the panel segment is relatively difiicult to bend, the tab is subjected to substantial bending forces during the upward movement of the handle portion thereof which tends to bend the tab about a transversely extending axis. Conventional tabs are unsatisfactory in this respect in that they are not sufficiently strong to withstand these bending forces. This problem becomes particularly acute when the removable panel is unusually large and when the residual thickness of the metal along the scoreline is relatively thick.

Conventional tabs for full panel pullouts often include an attachment portion which has a bottom wall with an aperture therethrough and a second wall extending upwardly therefrom. A front opening U-shaped lance is formed in the bottom wall. Lifting of the tab applies a force to this sloping wall through the bottom wall. Additional force is applied to the second wall during removal 3,411,662 Patented Nov. 19, 1968 of the panel following initial severance of the scoreline. These forces tend to cause structural failure or tearing of the sloping wall rearwardly of the ends of the lance. This problem is also particularly acute on large can ends or on can ends where it is necessary to maintain a relatively large residual along the scoreline.

Summary of the invention The present invention overcomes the above-noted disadvantages in that it prevents structural failure of the second wall of the attachment portion of the tab during initial severance of the panel and during removal of the panel following initial severance thereof. The present invention also provides a tab having high resistance to forces tending to bend the tab about a transverse axis.

The concepts of the present invention are particularly applicable to a tab of the type which includes a handle portion and an attachment portion having a bottom wall with an aperture therethrough and a second or sloping wall surrounding the bottom wall and extending upwardly therefrom radially outwardly of the aperture. The aperture is adapted to receive a rivet for attaching the tab to a removable panel of an easy-opening container. A generally U-shaped lance is formed in the bottom wall partially surrounding the aperture and opening forwardly. The U-shaped lance terminates in end portions to define a bend line in the bottom wall which extends generally between the end portions of the lance.

According to a first concept of this invention, the sloping wall of the attachment portion of the tab is firmly supported to prevent failure thereof. This supporting feature of the invention may be implemented by a tube support formed integrally with the tab and engaging the outer face of the sloping wall rearwardly of the end portions of the lance. More particularly, the tube support may be formed by turning a marginal portion of the tab adjacent the rearward attachment portion inwardly to form a tube support or bead which engages the outer face of the sloping wall. The forces described hereinabove that are applied to the sloping wall during initial severance of the scoreline and during removal of the panel tend to push or bend the sloping wall toward the bead. The bead, however, engages the outer face of the sloping wall to reinforce the latter so that it does not structurally fail when subjected to these forces.

Another feature of this invention is to strengthen the tab against bending about a transversely extending axis. This feature of the invention can be generally implemented by providing a peripheralbead along the longitudinal edges of the tab with the bead extending from the attachment portion to the handle portion of the tab. Desirably, this bead is the same bead that is used to support the sloping wall of the attachment portion.

The invention, both as to its organization and method of operation, together with further features and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings.

Brief description of the drawings FIG. 1 is a top plan view of a tab constructed in accordance with the teachings of the present invention and installed on an easy-opening container wall of the full panel pullout type.

FIG. 2 is an enlarged fragmentary plan view showing the tab and the surrounding portions of the easy-opening container wall. I

FIG. 3 is a fragmentary sectional view taken along line 33 of FIG. 2.

FIG. 4 is an enlarged fragmentary sectional view taken along line 44 of FIG. 2 and showing how the sloping wall of the attachment portion is supported.

FIG. 5 is a diagrammatic view illustrating the general direction of the forces that are applied to the tab during upward movement of the handle portion thereof to initiate severance of the removable panel.

FIG. 6 is a diagrammatic view generally illustrating the direction of the forces on the tab during removal of the panel following initial severance of the panel from the can end.

Description of the preferred embodiment Referring to the drawings and in particular to FIG. 1 thereof, reference numeral 11 designates an easy-opening container wall such as a can end having a relatively long sheet metal tab 13 constructed in accordance with the teachings of this invention attached thereto. The can end 11 is constructed of sheet metal and has a large circular rupturable scoreline 15 defining a circular removal panel 17. The tab 13 is secured to the panel 17 by a hollow rivet 19 formed integrally in the panel 17. Generally, the tab 13 has a handle portion 21, an attachment portion 23, and a rupturing portion which is engageable with the can end 11 at or closely adjacent the scoreline 15. The can end 11 is attachable to a container (not shown) by the usual peripheral flange 27.

Referring to FIGS. 2 and 3, the handle portion 21 of the tab 13 has a finger opening 29 therein. Portions of the tab 13 adjacent the finger opening 29 are bent outwardly to form an inner bead 31. The inner bead 31 lends strength to the handle portion 21 and also provides a smooth inner surface 33 for the opening 29.

A marginal or peripheral portion of the tab 13 is bent inwardly to form an outer bead 35 which extends over 180 degrees around the opening 29 and thence toward the attachment portion 23. Tabs such as the tab 13 inherently have a relatively weak section intermediate the attachment portion 23 and the handle portion 21. This weak section is generally represented in FIG. 2 by the transverse line or axis a-a. Tabs of this general construction tend to fail when subjected to bending forces about the transversely extending axis aa. With the present invention, however, the bead 35 extends continuously from the handle portion 21 across the axis a-a to the attachment portion 23. Therefore, the head 35 substantially strengthens the tab against bending about the axis a--a. The bead 35 generally strengthens the tab against bending forces about transverse axes including a second inherently weak area between the rivet 19 and the rupturing portion 25 lying generally along a bend line 73. It should be noted that the head 35 forms a complete tube (FIGS. 3 and 4) and, therefore, offers considerably more resistance to bending than would a mere straight downwardly extending flange.

To further strengthen the tab 13 against bending about the axis a -a, a pair of generally longitudinally extending ribs 37 and 39 are formed integrally in the sheet metal. The ribs 37 and 39 extend across the transverse axis aa to further increase the strength of the tab against bending. In the embodiment illustrated, the ribs 37 and 39 are formed upwardly (FIG. 3); however, the ribs could be formed downwardly, if desired.

The attachment portion 23 of the tab 13 includes a generally flat bottom wall 41 having an aperture 43 extending through a central portion thereof and a sloping wall 45. The sloping wall is spaced radially outwardly of the aperture and extends upwardly and radially outwardly from the bottom wall to connect the bottom wall 41 with a surrounding region 47 of the sheet metal of the tab 13. As best seen in FIG. 3, the surrounding region 47 lies above the bottom wall 41 and the hollow rivet 19 projects through the aperture 43 to secure the tab 13 to the panel 17. The angle formed by the walls 41 and is not critical and these walls could be perpendicular if desired.

The bottom wall has a generally U-shaped lance 49 therein. The U-shaped lance partially surrounds the aperture 43 and opens forwardly. The U-shaped lance 49 terminates in end portions 51 and 53. In operation of the device, lifting of the tab 13 causes the bottom wall 41 to bend about a bend line 55 which extends between the end portions 51 and 53 of the lance 49. Thus, the lance 49 and the bend line 55 define a tongue portion 57 of the bottom Wall 41.

The head 35 has an enlarged section 59' adjacent the attachment portion 23. As best seen in FIG. 4, the enlarged section 59 includes an upper wall portion 61, a peripheral wall portion 63, and a lower wall portion 65. The enlarged section 59 of the bead 35 terminates in a bead end or edge 67 which engages an outer face 69 of the sloping wall 45. Preferably, the lower wall portion is bent upwardly slightly adjacent the sloping wall 45 to allow the head end 67 to engage the sloping wall above the lower end thereof. As shown in FIG. 2, this engagement between the head end 67 and the sloping wall 45 continues through two equal arcs 0 on both sides of the attachment portion 23. The length of the arcs 6 may be varied depending upon the amount of reinforcement desired and in the particular embodiment illustrated, each of the arcs 0 is approximately 80 degrees. It is important, however, that this engagement between the bead end 67 and the sloping wall 45 exist immediately forwardly of the lance end portions 51 and 53.

Preferably, the bead 35 terminates in two ends 71 as shown in FIG. 2. As shown in FIG. 3, the rupturing portion 25 intermediate the two ends 71 is in the form of a relatively fiat downwardly extending flange. The rupturing portion 25 engages the scoreline 15 of the panel 17 closely adjacent the scoreline.

In the first phase of Operation of the tab 13, the user raises the handle portion 21 upwardly away from the panel 17. This causes the tab to bend about the bend line 55 to allow downward movement of the rupturing portion 25. As the upward movement of the handle portion 21 continues, the rupturing portion 25 forcibly engages the scoreline 15 of the panel 17 and ultimately initiates severance of the scoreline. In order for the tab to move upwardly any significant amount, and in order that the scoreline 25 can be ruptured initially, it is necessary that the panel 17 itself bend about a panel bend line 73 illustrated in phantom in FIG. 2. The bend lines 55 and 73 are generally coextensive for the length of the bend line 55. The scoreline 15 and the bend line 73 form a panel segment 75 which bends inwardly into the interior of the container about the panel bend line 73.

The forces on the tab 13 during this initial upward movement of the tab can best be understood by reference to ,FIG. 5. FIG. 5 diagrammatically shows the tab 13 being subjected to an upward force F1 by the user. The tab is hinged about the bend line 55 and the upward force F1 tends to pivot the tab 13 in the clockwise direction about the bend line 55. This tendency of the tab 13 to pivot about the bend line 55 is resisted by the panel 17 which exerts in upward force F2 on the opposite end of the tab. In order that the summation on the forces on the tab 13 in the vertical direction can be equal, a force F3 acts downwardly on the tab through the bend line 55. Physically, this force is applied to the bend line 55 by the tongue portion 57 of the tab 13 which is secured to the panel 17 by the rivet 19.

With reference to FIG. 4, it will be apparent that the force F3 acts downwardly against the bottom wall 41 generally along the bend line 55 substantially as shown. If it were not for the engagement of the bead end 67 with the outer face 69 of the sloping wall 45, the sloping wall and the bottom wall 41 would tend to bend or distort under the influence of the force F3. However, the head end 67 provides sufficient additional rigidity to prevent fracture or harmful distortion of the sloping wall 45 or of the bottom wall 41.

After the scoreline 15 is initially severed and the tab 13 has been raised to the desired angle, the user, in the second phase of operation of the tab, pulls upwardly and outwardly away from the can end 11 to completely remove the panel 17 therefrom. The forces on the tab 13 during this phase of the operation can best be understood by reference to FIG. 6. FIG. 6 diagrammatically shows the tab 13 hinged about the bend line 55 with the panel segment 75 bent inwardly. The tab (for purposes of illustration), is raised to an angle of approximately 45 degrees with the panel 17, it being understood that the tab can be raised to various angles depending upon the particular desires or requirements of the user.

As shown in FIG. 6, the user exerts an outward pull or force F4 on the tab 13 and in the plane of the tab. This causes an oppositely directed force F5 to be exerted in the plane of the tab against the bottom Wall 41 and the sloping wall 45 of the tab. The force F5 is applied to the tab generally along the bend line 55. It is apparent from viewing FIG. 4 that the force F5 also tends to push the bottom wall 41 and the sloping wall 45 forwardly and that such forward movement of the walls 41 and 45 is precluded by the engagement of the bead end 67 with the slopping wall 45.

Because both of the forces F3 and F5 tend to distort or fracture the walls 41 and 45 by pushing them forwardly, it is particularly desirable to have the bead end 67 engage the sloping wall 45 directly opposite the end portions 51 and 53 of the lance. However, support of the sloping wall 45 laterally of the lance 49 is also desirable.

It should be understood that FIGS. 5 and 6 show in a general way the primary forces acting on the tab and that these figures do not necessarily represent a complete force analysis. The bead 35 can be enlarged varying amounts at the section 59 or need not be enlarged at all.

Although exemplary embodiments of the invention have been shown and described, it will be apparent that one having ordinary skill in the art could make numerous modifications, substitutions and changes without departing from the spirit and scope of the present invention.

I claim:

1. A tab of the type attachable to a wall of an easyopening container to initiate severance of a segment of said wall comprising:

a tab body constructed of sheet material with the sheet material of peripheral regions of the tab body being curled to form peripheral reinforcing curl portions on opposite sides of the tab body to stilfen the tab body;

an attachment portion constructed of sheet material and joined to the tab body adjacent one end thereof with the other end of said tab body serving as a lifting end, said attachment portion being attachable to the container wall;

each of said peripheral reinforcing curl portions extending toward said one end of said tab body and at least partially around said attachment portion; and

a portion of the sheet material of said one end of said tab body being bent downwardly to form a rupturing flange for applying a force to the container wall upon moving of the lifting end of the tab body away from the container wall, said curl portions being interrupted sufficiently at said one end of the tab body to permit the formation of said rupturing flange.

2. A tab as defined in claim 1 wherein said tab includes a wall portion of sheet material for joining the attachment portion to the tab body and the curl portions adjacent the rupturing flange are turned to at least substantially abut said wall portion to support the latter.

3. A tab as defined in claim 1 wherein said rupturing flange is relatively straight and projects toward the container wall when the tab is attached thereto.

4. A tab of the type attachable to a wall of an easyopening container to initiate severance of a segment of said wall comprising:

a tab body constructed of sheet material and defining all of the periphery of the tab, the sheet material along peripheral regions of the tab body being curled to form peripheral reinforcing curl portions on opposite sides of the tab body to stiffen the tab body against bending forces;

an attachment portion constructed of sheet material and joined to the tab body adjacent one end thereof and lying within the periphery of the tab body with the other end of the tab body forming a lifting end, said attachment portion being attachable to the container wall;

hinge means for allowing said lifting end of the tab body to be moved away from the container wall to pivot said tab body about said hinge means to move said one end of said tab toward the container wall;

a portion of the sheet material at said one end of said tab body being bent toward the container wall to form a relatively narrow rupturing flange for applying a rupturing force to the container wall upon pivotal movement of the lifting end of the tab away from the container wall; and

said reinforcing curl portions extending respectively along said opposite sides of the tab toward said rupturing flange and at least partially around said attachment portion.

5. A tab as defined in claim 4 wherein said tab body has a sloping wall of sheet material joined to the attachment portion, the sheet material of the curl portions adjacent said rupturing flange being turned to abut said sloping wall to support the latter.

6. A tab as defined in claim 4 wherein said rupturing flange is relatively straight and projects toward the container wall when the tab is attached thereto.

7. A tab as defined in claim 4 wherein said curl portions extend toward said one end of said tab body at least as for said rupturing flange.

8. A tab of the type attachable to a wall of an easyopening container to initiate severance of a segment of said wall comprising:

a tab body constructed of sheet material and defining the complete periphery of the tab, the sheet material along peripheral regions of the tab body being curled to form peripheral reinforcing curl portions on opposite sides of the tab body to stiffen the tab body against bending forces;

an attachment portion constructed of sheet material and joined to the tab body adjacent one end thereof and lying within the periphery of the tab body with the other end of the tab body forming a lifting end, said attachment portion being attachable to the container wall;

hinge means for allowing said lifting end of the tab body to be moved away from the container wall to pivot said tab body about said hinge means to move said one end of said tab toward the container wall;

a portion of the sheet material at said one end of said tab body being bent toward the container wall to form a relatively narrow rupturing flange for applying a rupturing force to the container wall upon pivotal movement of the lifting end of the tab away from the container wall; and

said reinforcing curl portions extending respectively along said opposite sides of the tab toward said rupturing flange and terminating on opposite sides of said rupturing flange closely adjacent thereto.

9. A tab as defined in claim 8 wherein said tab body has a sloping wall of sheet material joined to the attachment portion, the sheet material of the curl portions adjacent said rupturing flange being turned to abut said sloping wall to support the latter.

10. A tab of the type attachable to a wall of an easyopening container to initiate severance of a segment of said wall, comprising:

an attachment portion constructed of sheet material and adapted to lie contiguous to the container wall;

a tab body constructed of sheet material and circumscribing said attachment portion, said tab body having a connecting wall adjacent one end thereof joined to said attachment portion and extending upwardly from said attachment portion whereby said attachment portion and said tab body are interconnected, the other end of said tab body defining a lifting end, the sheet material of said tab being sufficiently pliable adjacent said connecting wall and said attachment portion to define hinge means for allowing said tab body to pivot relative to said attachment portion whereby moving of the lifting end of the tab body away from the container wall forces a marginal portion of the tab body adjacent said attachment portion being turned inwardly to form a bead engageable with the outer face of said connecting wall adjacent said hinge means to reinforce said connecting wall to allow said connecting wall to resist said force without failure.

11. A tab as defined in claim 10 wherein said head terminates in a bead end and said head end engages said outer face of said connecting wall to reinforce said connecting wall.

12. A tab as defined in claim 10 wherein said bead includes two bead portions with said head portions extending from said one end of said tab body to said lifting end along opposite longitudinal edges of the tab body to strengthen said tab body against bending about a transverse axis.

13. A tab as defined in claim 10 wherein said head includes two spaced bead portions engageable with circumferentially spaced regions of said connecting wall and the sheet material of the tab body intermediate said bead portions is bent downwardly to define a rupturing portion for engaging the container Wall.

14. A tab of the type attachable to the wall of an easyopening container to initiate severance of a segment of said wall, comprising:

an attachment portion and a tab body constructed of a single piece of sheet material;

said attachment portion adapted to lie contiguous to the container wall and to attach the tab body to the container wall;

said tab body circumscribing said attachment portion and being integrally joined thereto adjacent one end thereof with the other end of said tab body defining a lifting end, the sheet material of said tab being sufiiciently pliable adjacent the juncture of said attachment portion and said tab body to define a hinge line which allows said tab body to pivot relative to said attachment portion whereby moving of the lifting end of the tab body away from the container wall forces said one end of said tab body against the container wall and applies a force thereto; and

the marginal regions of said tab body being turned inwardly to define reinforcing bead portions extending along the opposite sides of the tab body for at least substantially the full distance between said ends thereof and at least substantially circumscribing said attachment portion to thereby substantially stiffen said tab throughout the full length thereof against bending of said tab body about a generally transverse axis.

15. A tab as defined in claim 14 wherein said tab body has an opening therein sized to receive the finger of a user and the zone of sheet material of the tab body around said opening is curled to form an inner reinforcing head.

16. A tab of sheet material attachable with a rivet to an easy-opening container, said tab comprising:

a tab body of sheet material having a forward portion and a handle portion and defining a longitudinally rigid lever;

an attachment portion of sheet material joined to said tab body adjacent said forward portion thereof, said attachment portion having an aperture therein for receiving the rivet to attach the tab to the easyopening container;

said tab body having a connecting wall at said forward portion thereof to which said attachment portion is joined, the sheet material adjacent the juncture of the attachment portion and the connecting wall being sufficiently bendable to define a hinge about which said tab body can be pivoted relative to said attachment portion whereby lifting of said handle portion causes bending of the sheet material about saidhinge and applies a force to said connecting wall through said bottom wall; and

means for supporting said connecting wall forwardly of said hinge to strengthen said connecting wall to allow said connecting wall to resist said force without failure.

References Cited UNITED STATES PATENTS 3,303,959 2/1967 Brown 22054 3,322,296 5/1967 Khoury 22054 3,349,949 10/1967 Brown et al 220-54 THERON E. CONDON, Primary Examiner.

GEORGE T. HALL, Assistant Examiner. 

